- Escherich was based in Munich, Germany and was a pediatrician doing research on the bacteria of infant intestinal tracts

- Most strains of E. Coli are harmless and occur widely in nature and in gastrointestinal tracts of humans

- It is divided into main phylogenetic groups of A, B1, B2, D, and E. Its distinguished by genetic markers. These groups all developed from a common ancestor but branched off over time

- E coli is classified based on its surface antigens into serotypes and by its disease causing mechanism into pathotypes

- E coli can be found in Bergeys Manual

- Domain: Bacteria

- Phylum: Proteobacteria

- Class: Gammaproteobacteria

- Order: Enterobacterales

- Family: Enterobacteriaceae

- Genus: Escherichia

- Species: Escherichia coli

- It has a cytoplasmic membrane, peptidoglycan layer, outer membrane, periplasm, nucleoid, cytoplasm, ribosomes, plasmids, flagella, and pili

- In order to grow E coli needs Carbon, Nitrogen, Phosphorus, sulfur, and oxygen. Also the optimal temp for growth is 37 degrees celcius and a pH of 7.0 is required

- The best way to grow E coli is using nutrient rich media like Luria-Bertani broth

- Some strains contain plasmids

- E coli does contain antibiotic genes, 2 examples are bla genes: Inactivate beta-lactam antibiotics like penicillin and cephalosporins. Examples include blaTEM, blaSHV, and blaCTX-M and tet genes Confer resistance to tetracyclines. The tetA gene is frequently found in E. coli

- The E coli genome has been completely sequenced and mapped, fiirst published in 1997

- The genome has 4.6 million base pairs

- Capsule is a key virulence factor that protects it from host defenses like the immune systems and antibiotics

- Toxins cause severe complications like hemolytic-uremic syndrome, and enterotoxins

- exoenzymes are virulence factors that help pathogenic strains invade host cells and cause disease

- E. coli uses antigenic variation to change its surface molecules, allowing it to evade the host immune system and persist in the body. This variation can involve switching between different versions of adhesins like fimbriae (e.g., Type 1 and P fimbriae) or capsule antigens like the K1 and K5 capsules

- E Coli is positive for catalase, indole, methyl red, nitrate reduction, ONPG (ortho-nitrophenyl-β-D-galactopyranoside), and motility tests. It is also positive on the Triple Sugar Iron (TSI) agar test, showing an acid/acid/gas

- Catalase Positive

- Indole Positive

- Methyl RedPositive

- ReductionPositive

- ONPGPositive

- MotilityPositive

- Diagnostic tests for E. coli include stool cultures to identify the bacteria, Shiga toxin detection tests to find specific strains, and urinalysis or urine cultures for urinary tract infections. Other molecular tests like PCR can also detect the presence of specific E. coli genes

- Other lab methods include culture on specific agars and gram stains

- Diarrhea, Abdominal cramps, Nausea, vomiting, Fever, Fatigue, seizure

- E. coli can cause damage by producing toxins that harm the lining of the intestines and kidneys, leading to severe illness and complications like hemolytic uremic syndrome (HUS), which can result in kidney failure

- leukocytes, such as macrophages, monocytes, and neutrophils are recruited to the cite

- elicits both humoral and cell-mediated immune responses

- can contribute to autoimmunity

- Most mild infections resolve on their own with rest and fluids, but severe symptoms like bloody diarrhea, persistent vomiting, or signs of dehydration require medical attention

- Common chemotherapies for E. coli infections include antibiotics like ciprofloxacin, trimethoprim/sulfamethoxazole (TMP/SMX), and nitrofurantoin

- chills, fever, abdominal pain, and changes to the liver, nervous system, and blood counts

- Trimethoprim-sulfamethoxazole (Bactrim, 160/800 mg twice daily)

- Nitrofurantoin (Macrobid, 100 mg twice daily)

- Fosfomycin (as a single dose)

- 3-14 days

- No e coli vaccine for humans

- it can be transmitted through poor hand washing, contaminated food and shared objects

- E. coli can survive on fomites, which are inanimate objects like doorknobs, countertops, and cutting boards

- E. coli vectors are DNA molecules, most commonly plasmids, used to carry foreign genetic material into E. coli cells for cloning and protein production

- The epidemiology of E. coli is broad, as it is a common cause of urinary tract infections (UTIs), traveler's diarrhea, and potentially severe systemic infections

- There have been recent E. coli outbreaks, including a multi-state outbreak linked to McDonald's Quarter Pounders in 2024 and another outbreak linked to romaine lettuce in late 2024. Additionally, there are ongoing investigations into a recent outbreak in the Arizona State Fair and a separate one linked to raw milk cheese in Washington

- The overall E. coli bacteremia incidence rate is about 48 per 100,000 person-years

- Studies show 30-day case fatality rates of around 8–18%, while overall mortality rates for BSI can reach up to 37% in specific hospital settings

- E coli is a CDC notifiable disease

Range from 1 to 88 years

Median age of 28

Sex

(n=104)

40% female

60% male

Race

(n=96)

95% White

2% African American/Black

1% Native American or Alaska Native

0% Asian

0% Native Hawaiian or other Pacific Islander

2% reported more than one race

Ethnicity

(n=93)

89% non-Hispanic

11% Hispanic

State and local public health officials interviewed people about the foods they ate in the week before they got sick. Of the 81 people interviewed, 80 (99%) reported eating at McDonald's. Seventy-five people were able to remember specific menu items they ate at McDonald's, of which 63 (84%) reported a menu item containing fresh, slivered onions.

WGS showed that bacteria from sick people's samples were closely related genetically. This suggests that people in this outbreak got sick from the same food.

WGS analysis of bacteria from 94 people's samples predicted resistance to chloramphenicol, streptomycin, sulfisoxazole, tetracycline, and trimethoprim-sulfamethoxazole. These findings do not affect treatment guidance since antibiotics are not recommended for patients with Shiga toxin-producing E. coli infections.

FDA tested recalled onions and one environmental sample from a grower. Both of these samples tested positive for non-O157:H7 Shiga toxin-producing E. Coli.